Question: $9s + 10t - 2u + 4 = -3t + 9u + 5$ Solve for $s$.
Explanation: Combine constant terms on the right. $9s + 10t - 2u + {4} = -3t + 9u + {5}$ $9s + 10t - 2u = -3t + 9u + {1}$ Combine $u$ terms on the right. $9s + 10t - {2u} = -3t + {9u} + 1$ $9s + 10t = -3t + {11u} + 1$ Combine $t$ terms on the right. $9s + {10t} = -{3t} + 11u + 1$ $9s = -{13t} + 11u + 1$ Isolate $s$ ${9}s = -13t + 11u + 1$ $s = \dfrac{ -13t + 11u + 1 }{ {9} }$